There seems to be a concerted effort in Washington, D.C. to undermine the successful Iran nuclear agreement.

Last month, Senators Bob Corker (R-TN) and Bob Menendez (D-NJ) introduced a bill to impose new sanctions on Iran, primarily in response to its testing of ballistic missiles. The legislation coincided with the American Israel Public Affairs Committee’s (AIPAC) annual conference in D.C., which in the past, AIPAC has often used to amplify its calls for new sanctions against Iran that might advance its ultimate goal of regime change. But while these renewed calls for sanctions target Iran’s ballistic missile program on paper, there may be other motivations at work — namely undermining the Iranian nuclear agreement and scoring political points ahead of the 2018 elections.

Throughout the negotiations leading up to the agreement, some members of Congress were actively pushing new sanctions legislation against Iran in an effort to stymie the negotiations. The foundation of the negotiations, and the final agreement, was that the United States was willing to offer sanctions relief in exchange for Iran scaling back its nuclear program and allowing unprecedented inspections of its facilities. Thus, it’s a fair bet that the members of Congress calling for more sanctions at the time wanted to see the negotiations crash and burn. Some of them even said so, like Sen. Tom Cotton (R-AR) who proudly confessed that “the end of these negotiations isn’t an unintended consequence of congressional action. It is very much an intended consequence — a feature, not a bug.” Not surprisingly, Cotton is one of the original co-sponsors of the new legislation. Menendez and Corker, too, were vocal proponents and co-sponsors of new sanctions bills throughout the negotiations. After all, Iran bashing polls well across party lines.

Of course, Congress wasn’t alone in pushing for sanctions. In 2015, AIPAC used its annual conference to bolster its lobbying efforts on the Kirk (R-IL)/Menendez bill, the same legislation Cotton was speaking to, which would have imposed new sanctions on Iran at the height of delicate negotiations. In the summer of 2015, before and after the accord was signed, AIPAC sunk tens of millions of dollars into attacking it, arguing it would never work.

Today, it’s not just the introduction of new sanctions legislation that is threatening the deal. The hostile rhetoric towards Iran has also increased.

At this year’s AIPAC conference, House Speaker Paul Ryan (R-WI) used his speech to denounce the Iran agreement as “an unmitigated disaster.” Senate Majority Leader Mitch McConnell (R-KY) actually took the opportunity to promote war with Iran, claiming that in an attempt to keep all options on the table, the Obama administration “blurred the most important one, and that’s a determined military campaign to end Iran’s nuclear program.” Vice President Mike Pence echoed former National Security Advisor Michael Flynn’s February comments about putting Iran “on notice.”

Despite the naysaying and saber rattling — from Congress, the Trump administration, and AIPAC — more than a year since the implementation of the accord, the Iranian nuclear agreement is actually working exactly the way it’s supposed to. All of Iran’s potential pathways to obtaining nuclear weapons have been verifiably blocked. Its breakout time, the amount of time it would take Iran to produce enough enriched uranium for one crude nuclear warhead, has been pushed from about 2–3 months to more than one year. Should Iran at any point choose to pursue nuclear weapons, the international community would know about it with more than enough time to react.

But still, some conservative strategists are pushing for new sanctions for the express purpose of undermining the agreement. Shortly before President Trump took office, Michael Rubin, a resident scholar at the conservative American Enterprise Institute, told the Washington Post, “What’d I’d like to see is [the Trump administration] going along with the deal, but subtly antagonizing the Iranians enough so the Iranians want to scrap it… More non-nuclear sanctions. Pushing the [International Atomic Energy Agency] to inspect more. We can force them to be the ones to pull the trigger.”

More strategic opponents of the nuclear agreement argue that these sanctions aren’t meant to undermine the agreement, but are instead meant to compel Iran to stop testing ballistic missiles — despite Iran’s contention that the tests are unrelated to the agreement and in compliance with U.N. resolutions. That’s certainly the gist of AIPAC’s recent arguments in favor of new sanctions. The trouble with that logic is that both the Obama and Trump administrations have already sanctioned Iran in response to its ballistic missile tests, and Iran has continued conducting tests nonetheless.

As the successful implementation of the nuclear agreement demonstrated, diplomacy is a far more effective approach to compelling Iran to change its behavior than coercive sanctions. Iran’s nuclear technology program significantly expanded under the sanctions regime before President Obama and Iran’s President Rouhani agreed to explore diplomatic options.

Whether or not they supported the historic Iran agreement, lawmakers who now appreciate its value mustn’t be fooled by the legislative misdirection. Passing new sanctions would be a redundant and counterproductive measure, sure to be perceived by Iran as a de facto violation of the agreement. It could increase tensions with Iran in spite of its cooperation with the United States on a number of regional efforts and reverse progress in changing Iran’s behavior for the better.

Paul Kawika Martin is the senior director for policy and political affairs at Peace Action. In 2006, he received a rare visa to conduct a fact-finding mission in Iran. You can find him on Twitter @PaulKawika.